Disinformation related to science has been a major concern nowadays and the challenges to face it have intensified at a time when the world is going through a pandemic. The purpose of this article is to problematize and reflect on the ways in which the disinformation agenda has been constructed, seeking to discuss the threats to the democratic system. Through literature review and analysis of the Brazilian political situation, this article unfolds from the following axes: 1) cultural, political and ideological factors that make disinformation a fertile field for doubt and disbelief; 2) actions to deal with disinformation and its limitations. 3) the process of institutional disbelief brought about in a political scenario of epistemic contestation and the role of the media in this performance; 4) a hybrid war agenda established in the political and legal field, which threatens the current democratic system in the name of an undefined enemy: disinformation; Finally, this article seeks to offer a broad overview of the challenges and difficulties in the field of communication and information in addressing science-related disinformation in a current context of informational, political, legal and technological disputes